Google Play is an app marketplace managed by Google where users can upload their Android-compatible applications. Third party developers using Android software development toolkit can build applications as packaged binary application package files (“APKs”) and upload them to Google Play store for distribution to end users.
Through Google Play those apps can be found by end users, downloaded and installed on Android-based devices. Google additionally provides a set of services useful to implement common functionalities in Android apps, such as messaging, asynchronous notification, application upgrade, and in-app payment. We will call these as “Proprietary Google Services” or PGS. The same typically applies to other proprietary services (“PS”) owned by other companies.
Google Play is not the only possible distribution platform for Android apps. There are alternative marketplaces such as Amazon Store and alternative payment methods. Developers that want to also distribute through these alternative channels are forbidden to use PGS and therefore have to build a different APK package linked to alternative implementations of those services. This requires additional development efforts that usually discourage the use of alternative platforms and becomes a technical barrier to Google competitors.